Baghdad - Six people were killed and 20 others were injured in Iraq's Diyala province when a female suicide bomber detonated herself on Wednesday, the Egyptian State news agency (MENA) reported.

The bomber had targeted an Iraqi police patrol near a court in the restive provincial capital city Baquba, located some 66 kilometres north of the capital Baghdad, according to the report.

The number of casualties was likely to rise due to the congestion near the scene if the attack, an Iraqi security official told MENA.

The blast damaged several buildings and cars.

Diyala has witnessed over 20 female suicide attacks over the last few months, according to MENA.

Three Christians have been killed in the space of 24 hours in the northern city of Mosul, Aswat al-Iraq news agency reported Wednesday.

A man and his father were both shot dead Tuesday at their workplace, while extremists forced their way into a pharmacy in another district of the city and killed a Christian assistant who worked there.

Extremists killed a man and his father in September in the same city, which is located some 400 kilometres to the north of the capital and which is home to the second-largest community of Christians in Iraq after Baghdad.

Christians are persecuted because of their religion by the Sunni al-Qaeda in Iraq terrorist group and by the Shiite militias.

Churches and aid organizations in Europe have been pushing for European Union countries to accept Christian refugees from Iraq.

Christian communities within Iraq are divided over the issue of immigration, which has severely reduced their numbers.

The Chaldean Church has spoken out for EU countries to accept individual Iraqi Christian families in acute danger, but the church would also like to prevent one of the world's oldest Christian communities from disappearing.